Oral Cavity 05

This field shows two large papillae - circumvallate papillae - on the dorsal surface of the tongue (to the right); each has an A placed over the connective tissue core (lamina propria). The epithelium covering these papillae is of the NON-keratinized stratified squamous variety (B). Each papilla is surrounded by a deep cleft (C) or "valley" that is in fact a fluid-filled depression in the lingual mucosa. The fluid filling the valley or "moat" around the papillae is a mixture of the secretions of the major and minor salivary glands, as well as the serous secretions of a special set of serous glands (of von Ebner) seen at D. These serous secretions bathe the apical surfaces of the taste buds (E) that are found within the epithelium of the lateral sides of the papillae. Taste buds are neuroepithelial structures and are to be distinguished from the connective tissue papillae (F) that protrude into the surface epithelium but do NOT come in contact with the contents of the oral cavity.The region around "G" is shown at higher magnification in Oral Cavity 06.

Slide N-3, field Q40 of finder slide B, 2.5X objective